Convertible tire vulcanizer



Aug-24,1943- J. c; HE INTZ 2,327,639

CONVERTIBLE TIRE JULGANIZER Filed Jan. 22, 1940 Patented Aug. 24, 1943 7 Footwear 1511i: 'rIRE VUL ANIZER e v JamesCl Heintz, Lakewood, Ohio Atacam reiuiar fzz, 1940, Serial Nb. 314,928

' m l- Claims.

This invention relates to pn uma -tirelvub canizers, and more particularly those of the hinged or watch-case, type employed for retreadme, althou h not wh ll e ifin d ereto- The principal o j ct in i is topr v de, an improved, compa t appa ad p a t a W range of tiresizes, for perl o rming either shallow flan}; recapping with relatively-cold side pressure rings, or deep-.iiank recapping or full retreading with, vulcanizingside moldingsurfaces,

A further object is to provide improved tread} atr x and sid ng mountin s fo re a pin full retreading and new-tire treading vulcanizers. This application is a continuation, part, of my prior application for Art of retreading tires, Serial No. 311,151, filed December 27, l939, now Patent No. 2,228,212, as to mold features common to the two disclosures L I Of the accompanying drawing views,

in section, showing a horizontal hinged vulcanizer embodying my invention, fittedWithfdold side rings, in Operation on a tire. I

Fig. 2 is a partial vertical section on a larger scale, on the line 2-2of Fig. 1. g Y V Fig. 3 is a viewcorrespondingte.Pig. 2, Show:

ing the vulcanizer fitted with hot side ringsgthe cold rings being removed. ,7 I

Fig. 4 is a detail secticnalviewshowing a' modified matrix, I f

Referring at first toFigs. 1 andzfltls alower mold or vulcanizer section adapted to, be hori zontally supported on a floor by legs li', 121s a complemental upper section connected"at the back with the lower section by, the usual-hinge l 3 having vertically adjustable b'olts l l forvarjiably spacing the sections to accommodate difie'rent widths of tires. Each complete sectioncomprisesan integral cast-ironjbody and accessoi iesineluding "matrix members, etci; their fasten ings, and clamping devices. Thesectio-ns are adapted to befaste'nedtogether-upon the work by the usual pivoted side clampingbolts I 5 and a special pivoted clamping and mold-breaking bolt ltilat the front, as disclosed in my'prioriP-atents' 2,174,188 and. 2,174,189 of September. 26,-1939,

and application Serial No; 258,216,:filedxEebruary 24, 1939;1'10W'Pdt81lt No, 2,255,163. ,J

Fig. l is a plan View, partly broken faway fand Each mold section-i9 01 12"is-formed,withoa;

steam jacket ll for heating the 'tread matrices, and the side-wall matrices when present, :1 [3,318; are the usual interchangeable, segmental, main, tread-molding. matrix rings, formedwith:side. flanges to define the ,retreadsflanks, said in s preferably being made of alloynandll ais one of the usual interchangeable spacer rings of selected thickness, employed between the main rings when necessary to obtain a desired tread width, the spacer being radially .backed by an outer endless locking ring 20 carried on the lower mold section. The matrix rings and:spacer in this case fdefin a molding cavity f'orforming a full-width,shallow-flank recap. l

Each main matrix ring: 13 is peripherally formed with a 'radialeseating surface, preferably cylindrical and complemental to a fixed cylindrical matrix seat'2l formed on the inner wall oi the steam jacket Ii'LWhich partly embraces said seat.. The jacket Wallis further formed, adjacent to and radially inward of the seat? I, with a fixed -conical.tread-matrix seat 22, engaged by a complemental conicalseating face on the matrix ring IS, the cone angle being preferably of the order of 15-110 20 degrees to the central plane, as in my aforesaid Patent. 2,174,189, but here the radial widthof the seat 22 is, slightly less than the radially shallowest one of the interchangeable matrix rings [8 employed in the mold, to accommodate the cold and hot side pressure rings hereinafter mentioned; The segments oi the matrix rings 18 may. forexample, be three or four in number and those in the rear are inserted and re moved by a radial edgewise movementand. retained'bykey tongues and grooves, while the lockingjsegment [Stat the front, through which the Fi Zsection is taken, is insertible andremovable by anaxial movement between the adjacent front ends of the two rear matrix segments, and detachably retained by; vertical screw bolts 23. This matrix mounting is broadly described in said Patent 2,174,189 and the se ment retaining devices further'disclosed and claimed inmy aforesaid application Serial No. 258,216, new Patent No. 2,255,163p Other matrix retaining devices could be employed. p I

Radially inward of th conical matrix seat 22,

g each mold section is;formed with a seat 24 defining theinne r limit r said seat 22 and an adjoiningseat 25, these two defining a recess 26 and being shown respectively as cylindrical, and com.

cal with the same angle as the Satan, to obtain the best heat transmission, although such'shape is not broadly essential. The seats24, 25, are for mounting hot rings hereinafter-described in cennection with Fig. 3, and the recessi26 alternatively receives the peripherallip of a recapping side pressure plate orring 27. .The seats 2 and 25 are laterally embraced or overlapped by the radial inward portion of the steam jacket 11.

Ring 21 is detachably. mounted on an inner radial flange 28 ofthe mold section, laterally spaced from the inner edge of the seat 25 to define a mounting recess 29, and fastened by cap screws 30 whose stems pass through holes 31 in the flange, the hole rim constituting a' fastener member on the flange. The back of the ring 21 is formed with stiffening and heat-radiating flanges 32, both edges are exposed to the air, and its mountings on the flange 28 are of relatively small area, so that the ring remains relatively cold, below a vulcanizing temperature, during the retread cure. Hence it is termed a cold ring whose temperature is anything short of that which would vulcanize new rubber or melt or overheat old rubber, to distinguish from a hot ring or cavity wall maintained at a vulcanizing temperature. The inner tire-confining surface of ring 21 is mostly flat, but that of the outer rimorlip'; accommodated in the recess 26, may be slightly curved or coned inwardly toward the opposite ring 21 to better confine the tire shoulder flank, Each ring-attaching post may have a spacing washer 33 in its joint with the flange 28, but suchspacers are usually not required when the mold cavity ineluding said ring-is properly related to the size of the tire under treatment.. The tire 34 with retreading rubber 35 thereon is shown in the mold in Figs. 2 and 3, containingthe,usualair bag 36 and mounted on a suitable curing rim 31..

With the alternativeside pressure-ring equipment illustrated in Fig. 3, the recapping cold rings 21. of Figs. 1 and 2 have been removed and in theirplace, in each mold section Her 12, is mounted a hot vulcanizing side matrix or pressure ring 38 whose outer. seating faces. closely conformv to the seats 24,. 25, and whose innerv surface forms a radial inward continuation of the tread matrix seat 22, closely'confining the tire side wall substantially at the middle and around the shoulder flank, for vulcanizing aradially-deep recap rubber wing 35 or vulcanizing. side-wall rubber down to about the middle ofthe'tire side in a'full retread where the old'rubber tread has been stripped fromthe carcass.

order of fifteen degrees like thatofthe treadmatrixside and its seat, conforming'substantially to the average tire shoulder flank-iangle, so as to support the shoulder flank-withiminimum distortion. 1

Vertical bolts 39, which are carriedthrough radial slots 40 in the mold section or l2,detachably fasten each hot ring 3B upon its mold section. In the outer endsofthe four forward ones of said slots are also received'the stems of the bolts 23 for fastening the axially inserted segment l8 of the main matrix ring l8. The inner rim of each hot-ring carriesa non-vulcanizing or relatively cold side'pressure ring M of the general character covered inmyprior Patent No. 1,810,963 of- June 23, 1931, fastened to the hot'ring by cap screws 42, and having a narrow insulating spacing from the hot ring throughout most of their common area, said cold ring also being formed "with a' trough 43' for receiving cooling water when required. 7

' In the modification of Fig. 4, the side flange 18 of each matrix ring I8 is inwardly offset laterally from the; plane of the tire-side-shoulder flank,

' to define the 'edgefof aconventional shallowflank recap narrower than the original tread.

In operating this apparatus for shallow-flank recapping, the mold is set up as in Figs. 1 and 2,

with the proper cavity diameter and width of v The outer mar.- ginal portion 38 of the tire-confining face of ring 38 is substantially conical, with an-angle of thetread matrix l8, etc., to accommodate the particular tire without harmful distortion, and. with cold side pressure rings 21 of the proper spacing mounted on the flanges 28 to accommodate the tire with but a slight flattening or distortion of its sides. The rim-mounted and slightly inflated tire 34 with top-cap vulcanizable rubber 35 applied to the roughened and cemented old tread rubber is then placed in the lower mold section in, the upper section 12 is closed and clamped upon the lower sectionand the contained work, i

the tire is inflated to full curing pressure and the vulcanization proceeded with in the usual manner, followed by removal of the recapped tire. Accommodation of the pressure rings 21 in the recesses 26, in a mold which is adjustable for substantial variations of tire width, provides a large width capacity without extreme tire-wall I distortion.

For a deep-flank recap over the carcass and remains of the old tread and side-wall rubber as indicated in Fig. 3, or for a full retread preceded by stripping off oftheold tread and sidewall rubber down to about the middle of the tire sides, the cold rings 21 of Figs. 1 and 2 are removed and in their places are mounted thehot rings 38 carrying inner marginal cooling rings 4|. The radially-outward margins of said rings 38 then overlapthe radially-inward margins of the tread matrix rings -18, which are inset into their molding faces as shown, to form subtantially continuous shoulder-flank and 'outersidewall molding and vulcanizing surfaces. The apparatus of Fig. 3 could be employed, if-desired, with suitable alteration omitting the cooling rings 41 and substituting inner sidewall and bead vulcanizing hot molding surfaces of familiar character, for vulcanizing new tires, or the apparatus could be used as shown in Fig. 3, for vulcanizing the tread and outer side-wall rubber upon a'previously vulcanized newcarcass in-- eluding inner side-wall rubber, in a two-stage process. 55

To those skilled in theart, it Willbe evident from the foregoing that this invention provides a superior convertible vulcanizer for recapping pneumatic tires, or for treading or retreading' new or used tires. The form of the described embodiments could be considerably varied without departing from the scope of the invention as definedv in the claims. f

I claim: I v i V 1. A pneumatic-tire treading vulcanizer which comprises two annular sections each' of which comprises a tread-molding matrix,,a side-molding matrix and a heating jacket'embracing' the me, on the heating jacket seats for th'eitread-j' molding matrix and adjacentfthereto and, fa

dially-inward thereof 'seatsfor the side-molding I matrix, the seats for the tread-molding matrix comprising a substantially cylindrical surface and adjoiningit asubstantially conical surfaceat an,

angle ofpth e order of 15' to 20 degrees toithe V centralplane dividing the sections;

2. A pneumatic-tire retreading vulcanizer which comprises twolaterally adjustable annular sections, each of which sections comprises iaside molding matrix, 'a tread-molding matrix and 3 a steam jacket embracing the same, and adjoining seats separately recessed'in the jacket forthe side-molding: matrix. and. the ,itreademolding matrix, theseat' for the tread-molding matrix comprising a substantially cylindrical/surface. and a substantially conical surface at ananglei of the order of to degrees to the central plane dividing said sections.

3. A vulcanizer according to claim 2 having a tire-side confining cold pressure ring radially inwardly of the side molding matrix and secured thereto.

4. A pneumatic-tire retreading vulcanizer which comprises two laterally adjustable annular sections, each of which sections comprises a steam jacket, a tread-molding matrix and a side-molding matrix with inner surface adapted to contact the tread and sides of a tire, seats for the matrices separately recessed into the steam jacket, seating surfaces on the matrices complemental to said seats, the seat for the tread-molding matrix comprising a substantially cylindrical surface and a substantially conical surface at an angle of the order of 15 to 20 degrees to the central plane dividing said sections, and extending inwardly beyond the seating surface of the treadmolding matrix a seating surface on the sidemolding matrix for an extension of the treadmolding matrix with an inner surface complemental to a portion of the inner surface of the side-molding matrix.

5. A pneumatic-tire vulcanizer which comprises two laterally adjustable annular sections, each of which sections comprises a tread-molding matrix and a side-molding matrix and a steam jacket embracing the same, seats for said matrices separately recessed into the jacket, complemental seating surfaces on the matrices, the seat for each matrix comprising a substantially cylindrical portion and a substantially conical portion at an angle of the order of 15 to 20 degrees to the central plane dividing said sections.

6. A pneumatic-tire vulcanizer which comprises two laterally adjustable annular sections, each of which sections comprises, a tread-molding matrix and a side-molding matrix and a steam jacket embracing the same, and on the steam jacket a radially cylindrical seat for the side-molding matrix and laterally adjacent and radially outward thereof a substantially conical seat for the tread matrix at an angle of the order of 15 to 20 degrees to the central plane dividing said sections. a

7. A pneumatic-tire retreading vulcanizer which comprises two laterally adjustable annular sections each of which sections comprises a treadmolding matrix, a side-molding matrix and heating means therefor, seats on the heating means and complemental seats on the matrices, a substantially cylindrical seat on the heating means for the side-molding matrix and adjoining the same a substantially conical seat for the treadmolding matrix at an angle of the order of 15 to 20 degrees to the central plane dividing the sections.

8. In a pneumatic-tire retreading vulcanizer a tread-molding matrix and adjoining the same a side-molding matrix, complemental surfaces on the matrices where they join, and adjacent said complemental surfaces on the tread-molding matrix a substantially conical seating surface adapted to contact heating means, the molding surface of said side-molding matrix adjacent said complemental surfaces being substantially parallel to said conical seating surface.

9. A pneumatic-tire vulcanizer which comprises two annular sections, each of which sections comprises a steam jacket and a side-molding matrix seated thereon, said matrix being adapted to be heated by the jacket through a substantially conical seat and an adjoining substantially cylindrical seat on the jacket and through complemental adjoining seating surfaces of the matrix.

10. A pneumatic-tire treading vulcanizer which comprises two separable annular sections, each of which sections comprises two matrices and a steam jacket with seats thereoncomplemental to seating surfaces of the matrices and with the matrices seated thereon, one of the matrices being a tread matrix adapted to vulcanize a portion of the tread of the tire and the other matrix being i a side-molding matrix adapted to vulcanize at least a portion of the side wall of the tire, the seating surfaces of the tread matrix comprising a substantially cylindrical seating surface and an adjoining substantially conical seating surface, and the seating surfaces of the side-molding matrix comprising a substantially cylindrical seating surface and an adjoining substantially conical seating surface, the conical seating surface of the tread matrix and the substantially cylindrical seating surface of the side-molding matrix meeting in a line substantially nearer the tire than the line of union of the seating surfaces of each individual matrix whereby the area of each matrix heated by contact With the steam jacket through said seating surfaces is large with respect to the volume of the respective matrices.

11. A pneumatic-tire vulcanizer which comprises two laterally adjustable annular sections, each section comprising a steam'jacket, a sidemolding matrix seated thereon and a tread-molding matrix seated on the jacket, the entire inner surface of the side-molding matrix adjacent the tread-molding matrix being cut away to form a seat for a flange on the tread-molding matrix, said tread-molding matrix being provided with an inwardly projecting flange seated thereon so as to form a molding surface for a portion of the side of a tire in addition to forming a molding surface for a portion of the tread of the tire so that by using the same side-molding matrices tires of different sizes may be vulcanized by lateral adjustment of the annular sections and the use of appropriate tread matrices.

JAMES C. HEINTZ. 

